   
   The streams generated by (where) return the value of expr: truthy if expr
   matched the given event, and falsey otherwise. This means (where (metric 5))
-  tests events and returns true if their metric is five."
+  tests events and returns true if their metric is five.
+  
+  Note that tagged, tagged-all & tagged-any can only be used with a single tag."
   [expr & children]
   (let [p (where-rewrite expr)
         [true-kids else-kids] (where-partition-clauses children)]

(defn tagged-any
  "Passes on events where any of tags are present. This stream returns true if
  an event it receives matches those tags, nil otherwise.

  (tagged-any \"foo\" prn)
  (tagged-all [\"foo\" \"bar\"] prn)"

  "Passes on events where all tags are present. This stream returns true if an
  event it receives matches those tags, nil otherwise.

  Can be used as a predicate in a where form, but only for
  testing a single tag.

  (tagged-all \"foo\" prn)
  (tagged-all [\"foo\" \"bar\"] prn)"
  [tags & children]
